Answer:
[tex]f(x)=\left(x-9\right)^2-\frac{220}{3}[/tex]
Step-by-step explanation:
Take the coefficient of ''x'', divide it by two, and squared it:
[tex](\frac{-18}{2})^2=81[/tex]
Now, add and subtract this value and re-organize on the standard form:
[tex]f(x)=a(x-h)^2[/tex]
[tex]\begin{gathered} f(x)=x^2-9x+\frac{23}{3} \\ f(x)=x^2-9x+81+\frac{23}{3}-81 \\ f(x)=\left(x-9\right)^2-\frac{220}{3} \end{gathered}[/tex]
